Did I say that Kirby damages carpet?
No.
Have I referred to Riccar in my responses?
No.
I did mention "in my experience," which you seem to ignore quite obviously.
Where CRI is concerned, marketing and organisations go hand in hand with brands and offer up convenient data based on using approval stamps that one day may well be disproved. It isn't unusual to find why consumers are questioning how a bagless upright can claim to have a Allergen seal of approval when the air gets dirty again as dirt gets chucked into a bin, for example.
Carpet wear is not just viewable from the top surface. Constant going over with an upright loses the underlay tread underneath, or to be more simple, the actual stitching in place on the back of the carpet. Some uprights offer a seal of suction and a brush roll WITH a protecting edge that allows carpet wear to have less damage over a longer period of time. True the brush roll plays a big part in it, but stiff bristles aren't stiff for long, they do wear down after a while.